TheStreet.com Ratings provides exclusive stock, ETF and mutual fund ratings and commentary based on award-winning, proprietary tools. Its "safety first" approach to investing aims to reduce risk while seeking outperformance on a total return basis.TheStreet.com's stock-rating model upgraded Ameristar Casinos ( ASCA) to "hold." The company owns and operates casinos and hotels in the U.S. The numbers: First-quarter revenue decreased 3% to $316 million as the company swung to a net profit of $30 million, or 52 cents per share, from a net loss of $60 million, or $1.07 per share, in the year-earlier quarter. The operating margin improved from 16% to 22% and the net margin climbed out of negative territory to 9%. Ameristar's financial position is weak. The company holds just $92 million of cash reserves, amounting to a low quick ratio of 0.6, and has $1.6 billion of debt. A debt-to-equity ratio of 4.5 indicates excessive leverage. The stock: Ameristar Casinos has surged 127% in 2009, outperforming all major U.S. indexes. The stock offers a 2.2% dividend yield. The model upgraded Cognizant Tech Solutions ( CTSH) to "buy." The company provides information-technology consulting and services and outsourcing services in North America, Europe and Asia. The numbers: First-quarter revenue ascended 16% to $746 million as net income improved 11% to $113 million and earnings per share climbed 12% to 38 cents. The operating margin increased from 17% to 19%, but the net margin dropped from 16% to 15%. Cognizant has an ideal financial position. Its balance sheet holds $808 million of cash reserves, which translates to a high quick ratio of 4.1. And the company has financed itself entirely with equity, so it has no debt obligations or interest expenses. The stock: Cognizant has surged 63% in 2009, outperforming all major U.S. indexes. The stock trades at an expensive price-to-earnings ratio of 20 and doesn't pay dividends.